Combined multi-way valve and combined multi-way valve control system

Abstract

A combined multi-way valve comprises a head unit, a tail unit and a plurality of sets of working units. Each working unit is provided with a set of paired working oil port A and working oil port B. The head unit comprises a valve body, a valve element and a feedback channel. A first cavity and a second cavity are formed in the valve body. A first feedback port of the feedback channel selectively communicates with a set of working oil port A and working oil port B, and a second feedback port of the feedback channel is connected with an external variable pump. A throttle valve is mounted on thefeedback channel to transmit load feedback pressure of each working oil port A or working oil port B to the external variable pump. An electric proportional flow valve is mounted between the first feedback channel and an oil return port of the valve body to adjust load feedback pressure in the feedback channel. The invention further provides a combined multi-way valve control system. According tothe combined multi-way valve and the combined multi-way valve control system, the electric proportional flow valve is used to stabilize the load feedback pressure in the feedback channel in the combined multi-way valve, so that output flow of the external variable pump is stable, and it is ensured that an executing mechanism is harmony in action, stable and good in operating performance.

Description

technical field [0001] The invention relates to the field of engineering machinery, in particular to a combined multi-way valve and a combined multi-way valve control system. Background technique [0002] In the field of construction machinery, especially in excavators, load-sensitive multi-way valves are widely used. The actuators of excavators are mainly driven by hydraulic cylinders and hydraulic motors. During excavation operations, it is necessary to distribute flow to different actuators. At present, in excavators A load-sensing system is used for flow distribution control. The load-sensing system is composed of a load-sensing multi-way valve and a load-sensing pump to realize flow distribution. The load-sensing valve feeds back the highest pressure of multiple loads to the load-sensing pump through the load feedback oil circuit, and adjusts the load-sensing pressure signal according to the load-feedback pressure signal. The displacement of the pump to output the flow...

AI Technical Summary

Problems solved by technology

[0008] The purpose of the embodiment of the present invention is to propose a combined multi-way valve and a combined multi-way valve control system on the basis of the existing load-sensitive multi-way valve, which can solve the problem of the load-sensitive multi-way valve in the prior art. The problem of unstable and uncoordinated action of the actuator caused by the instability of the load feedback pressure in the load feedback loop of the load-sensing multi-way valve

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